From a November, 2004 report on Cyclingnews:

Merckx dispels health rumours
Eddy Merckx's dramatic weight loss this year has given rise to much speculation as to whether he was seriously ill. The Cannibal, who is now looking almost as lean as he did in his racing days, told Sportwereld.be that there is nothing to worry about. "I underwent an esophagus operation on May 12," he said. "I have suffered with that since I was young. If I had have been born with a normal stomach, then I might have had an even better career. Some journalists asked me whether I had cancer. When I lay on the operating table I weight 110 kilograms. Since the end of August, my weight has stabilised at 82 kilograms. Logically it was a number of months before my body started working normally again, and in that time I lost a lot of weight."

http://www.cyclingnews.com/news.php?...ov04/nov29news